在柔软的子酸连接体Sb(III) 复合体中的立体化学 (非) 活性单一对
Mads Sondrup Møller1, Vickie McKee2, Christine J McKenzie1
1Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5320 Odense M, Denmark. mckenzie@sdu.dk.
Dalton transactions (Cambridge, England : 2003)
|March 31, 2025
概括
双同质抗复合物与酸 (TMe) 存在作为五或六协调的异构体. 这些抗 (III) 复合物在溶液中表现出异构和流动性行为,受反离子和温度的影响.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 协调化学 协调化学
背景情况:
- 已知有抗 (Antimony) 复合物与酸 (Hydrotris) (3-methyl-2-thiooxoimidazolyl) 酸 (TMe) 连接物.
- 这些复合体可以表现出不同的协调几何形状.
研究的目的:
- 研究TMe.的双同质抗复合物的结构多样性和溶液行为.
- 了解影响异构体形成和连接体交换动态的因素.
主要方法:
- 结晶以分离不同的异构体.
- 可变温度1H-NMR和11B-NMR光谱学用于研究溶液动态.
- 密度函数理论 (DFT) 计算以评估异构体之间的能量差异.
- 电子定位函数 (ELF) 图为分析单一对立体化学.
主要成果:
- 确定了[Sb(TMe) 2+的两个异构体:一个五度协调的[Sb(κ3-TMe) ]+和一个六度协调的[Sb(κ3-TMe) ]+,其异构体取决于对抗离子.
- [Sb(TMe) 2+在溶液中表现出流动性行为,在协调和反离子TMe联体之间进行联体交换.
- DFT的计算显示了两种异构体之间的能量差异很小.
- ELF图表表明,Sb(III) 上的立体化学活性单一对会影响五坐标异构体的几何,但不会影响六坐标的异构体.
- 额外的四核和二金属复合物在结构上得到了特征.
结论:
- 反离子在确定双同质抗复合体的协调几何学方面发挥着至关重要的作用.
- 含有TMe连接体的抗 (III) 复合体在溶液中表现出动态行为,包括连接体可变性和交换.
- 单一对Sb(III) 的立体化学活性依赖于形状,并影响观察到的结构.
相关概念视频
04:01VSEPR Theory and the Effect of Lone Pairs
Effect of Lone Pairs of Electrons on Molecule Geometry
02:51Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...